The present invention relates to distal radial ulnar joint (DRUJ) reconstruction in wrists of patients.
One treatment of chronic DRUJ dislocation is known as the Sauve-Kapandji procedure, as disclosed in "Nouvelle technique de traitment chirurical des luxations recidivantes isolees de l'extremite inferiure de cubitus. (Journal de Chirurgie, 47:589-594.) FIG. 1 shows a patient's wrist 10, distal portions of the radius 11 and ulna 12, a segment 13 of the ulnar neck 14 being excised (a proximal ulnar stub or stump 15 and a distal ulnar fragment 16 being formed). Radio-ulnar articular surfaces (not shown) are decorticated down to cancellous bone, and joint fusion is performed using a cancellous bone screw 17 and material 18 of the excised segment 13 between the facing joint portions to maintain the normal radio-ulnar diameter of the wrist. This operation is commonly used to treat post traumatic incongruity or arthritis of the DRUJ.
Although details of the operative procedure have been refined, the most common complication of the Suave-Kapandji procedure is proximal ulnar stub instability with symptomatic "popping" or "clunking" at the ulnar resection site. Also, the instability of the proximal ulnar stump 16 results in reduction of the spacing from the radius 12 (as shown by solid lines in FIG. 1) that is caused by connective tissue between the radius and the ulnar stump 16, and can produce ulnar impingement syndrome in some cases. Such complications have been observed in up to one-third of patients, and may persist, being major disadvantages of the procedure.
U.S. Pat. No. 5,108,444 to Branemark discloses a joint reconstruction system wherein the distal extremity of the ulna is completely removed and replaced with a guide body that is fastened to the radius and a control element that is fastened to the ulnar stump, the element movably engaging a slot that is formed in the guide body. A major disadvantage of this system is loss of ulnar support for the wrist.
Thus there is a need for a system for reconstruction of the DRUJ that overcomes the disadvantages of the prior art.